The Encapsulation Optimization Of Thermal Storage Material And Application Effect In Rural Building Of Cold Region

Intermittently heating is widely used in northern cold rural areas by hot wall and heated kang, but those heating styles can’t meet the need of the farmers because of the poor storage of the building materials and the low energy efficiency. Phase change materials(PCM) can absorb and release heat in transition process which improved the thermal efficiency and operating factor of energy, so PCM is widely researched in resent years and becomes one of the most popular application prospect of heat storage materials. We optimize and improve the defects existing in the previous encapsulation of the heat storage materials. Then we tested and evaluated the effect of temperature adjustment by laboratoy room and actural room. Then it can provide the basis for being widely used in the actual rooms. The main works in this thesis as follow:(1) Simulation study in actural rooms.We simulated the the way how the hot wall transfered heat by using ABAQUS finite element analysis software. We set the temperature for 200℃,heating time for 5h,and time after stopping heating for 4h. It found that the temperature in PCM went up more slowly than that in red brick, and went down more slowly when it stopped heating. So it showed PCM “Reducing peak and filling valley ”.(2) Solved the volume deformation problem in encapsulation caused by PCMchanging phase.In order to solve the low heat absorption rate during the heating stage and the high heat release to the hot wall interior during the heating rest stage, one double surface fin with a heat conducting- insulating switch was developed as an optimization design for phase change material macro package box which can be applied into the hot wall of building. The optimized phase change material macro package box was installed into a small laboratory room for the simulating experiment of hot wall heating. The influences of package box number, heating time, heat insulation layer thickness and other parameters on the temperature adjustment effect of phase change material were investigated. The results show that under the same conditions, the room temperature adjusting effect of phase change material is better and the room temperature becomes more stable with the increasing phase change material boxes installed in hot wall and the heating time prolonged. The improved phase change material macro package box with the developed double surface fin delays the room temperature decrease during the heating rest stage and improves the heat storage and temperature adjusting effect of phase change material.(3) Improve thermal efficiency storage and control heat transfer.A new type of heat radiators was fabricated by sealing a kind of phase change materials(PCM) in a macro encapsulation container with a set of fins which were attached to the main body through glide wheel and hinges. When the fins were on, they absorbed more heat; when the fins were off, the rock wool covered the fins so that it prevented the heat lost through the chimney.(4) Experimental study in actural rooms.We found an actural room which used hot wall for heating style in cold area. And we installed the box on the hot wall. Thus, we could use TRM-WD120 temperature measurement system and testo875-2i thermal imaging system to monitor the temperature change. We found that the more boxes we used, the more copper mesh numbers in box and the more time we heat the wall, the temperature in the room raised. PCM could adjust the temperature in the actural room.